Electron discharge device



Jan. 18, 1944. c. HERZOG 2,339,402

I ELECTRON DISCHARGE DEVICE Filed Dec. 24, 1942 I 9P '1 m I: 14 -19 i 17'; 5 1.17

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Zmventor CFARL HeqzoG;

attorney Patented Jan. 18, 1944 ELECTRON DISCHARGE DEVICE Carl Herzog, Bellevillc, N. J., assignor to Radio Corporation of America, a corporation of Dela- Application December 24, 1942, Serial No. 469,999

7 Claims.

My invention relates to electron discharge de vices, particularly to means for joining the electrodes to lead-in conductors in such devices.

Typica1 radio tubes usually comprise an assembly of concentric tubular electrodes, including a cathode, an anode, and one or more grids supported at their upper and lower ends by insulating spacers. The ends of grid side rods, cathode tabs and anode ears are usually aligned and project through the bottom spacer and are connected by separate small metal connectors, tabs or straps to the inner ends of the lead-in conductors in the tube header or stem. The operation of placing these connectors in proper positions with tweezers and Welding them in place is slow and tedious, and adds materially to the cost of the finished tube, particularly where the tube has a large number of electrodes and a small spacing between the header and the electrode assembly. The current conducting paths of the connectors between the contact pins and the electrodes criss-cross pro-- miscuously and their relatively long length, re quired by the relatively large header-to-electrode spacing, is undesirable for electrical reasons, particularly when current of ultra high frequencies flows in the connectors.

An object of my invention is an improved electron discharge device having short, orderly, and easily assembled electrode connectors.

A more specific object of my invention is novel connectors for joining electrodes to lead-in conductors.

Another object of my invention is a new method of joining electrodes to lead-in conductors in the manufacture of electron discharge devices.

Another object of my invention is an improved electron discharge device having shortened electrical paths between the contact pins and electrodes of the devices.

The characteristic features of my invention. are defined in the appended claim and one embodiment thereof is described in the following specification and shown in the accompanyin drawing in which,

Figure 1 is a longitudinal sectional view of an electron discharge device embodying my invention,

Figure 2 is a, horizontal sectional view taken along the line 22 of Figure 1, and

Figure 3 is a detailed view of a partially completed connector assembly of my invention.

The electron discharge device chosen for illustrating my invention and shown in section in Figur 1 comprises a tubular glass envelope I closed at its lower end with a conventional glass trimmed to a uniform length. The exhaust tube 4 in the particular tube shown communicates with the center of the header and is covered with a metal thimble 5, conveniently used as a centering lug, attached to the header and exhaust tube with cement.

The electrodes shown, including a cathode 6, grids I, B and 9 and anode l0 concentrically arranged and supported at their ends in insulating spacers El an I2 constitute a unitary electrode assembly. The insulating spacers may be reinforced with metal plates l3 and I 4 attached to side braces l5 and [6, which in turn are attached at their bottom ends to spuds Or short metal pieces I! and I8 embedded in the glass of the header. The lower end of the cathode and at least one of the grid side rods of each grid and a plate tab or ear, not shown, extend below the lower spacer and serve as terminals for these electrodes. The electrode terminals are joined to the inner ends of the lead-in conductors by a plurality of ribbon-like metal connectors l9 disposed in the plane of the inner ends of the conductors, the connectors extending in a general radial direction from the ends of the circularly arranged conductors to the electrode terminals.

In manufacture, the electrode assembly and the header with lead-in conductors are separately made, the two assemblies then being brought together and the proper electrode-to-conductor connections completed before the envelope l is teiescoped over the electrodes and sealed to the rim of the header. The inner ends of the conductors are cut to a uniform and relatively short length, the ends then being squared and polished with a grinding or cutting wheel passed across the conductors parallel to the header disc. A separate flat disc of sheet metal, Figure is die cut or blanked out so that a plurality of substantially flat ribbons (connectors l9), disposed in the plane of the disc, and extending generally radially of the disc, and held as a unit by the integral rim portion 2% of the disc, are formed. This unitary assembly of connector ribbons is held to bring the inner ends of the ribbons against the electrode terminals whereupon welded connections are easily made between the ribhens and terminals. It is not necessary, as heretofore common in radio tube manufacture, for the operator to insert her welding tools and tweezers into the confined space between a header and electrode assembly to make terminal connections. Then with all of the connector ribbon-to-terminal connections completed the operator places the assembly over the header with the rim of the metal disc resting on the smooth fiat ends of the lead-in conductors. By slight rotation the outer ends of each connector may be brought into registry with the ends of the conductors, with a fiat side of each connector overlapping and lying on the fiat end of a conductor, whereupon spot welds are made between the conductors and the connector. The electrical energy for such welding may conveniently be applied by attaching one terminal of the welding current source to a jig or chuck which holds all of the contact pins at their outer end and by pressing a small welding electrode, connected to the other terminal of the source, against the upper side of the connector over the conductor. If desired, several or all of the welds may be made simultaneously. Mounting operations are completed by cutting away the portions of the thin metal ring between the conductors. Removal of the now unwanted pieces of metal may be facilitated by scoring the metal along the dotted lines shown in Figure 3.

Good results have been obtained in manufacturing electron discharge devices of the radio receiving type having a bulb diameter of about one inch, having headers with 8 lead-in conductors of .050 inch diameter nickel-iron wire and having connectors IQ of .005 inch nickel. It s found desirable to stiffen the connector ribbon by crowning or embossing lengthwise channels. Tubes constructed according to my invention are characterized by the orderly appearance of the electrode connectors and by the close spacing between the header and the lower end of the electrode assembly. If desired the lead-in conductors may be trimmed by grinding substantially flush with the upper surface of the glass header.

I claim:

1. The method of making an electron discharge device having a glass disc with a plurality of spaced parallel circularly arranged leadin conductors sealed perpendicularly through the glass disc, and a unitary electrode assembly with terminals for the electrodes arranged in substantially a straight line across one end of said assembly, comprising cutting off all of said conductors a uniform and relatively short distance from said header disc, then blanking out a plurality of connected substantially flat ribbons from the center portion of a single flat disc of sheet metal so that the ribbons are disposed in the plane of the metal disc and extend generally radially of the metal disc and are held as a unit by the integral rim portion of the metal disc, then welding the inner ends of the ribbons to the electrode terminals, placing the rim of the metal disc on the ends of the conductors and rotating to bring the outer ends of the ribbons in registry with the ends of the conductors, welding the end of each conductor to said rim and finally cutting away the rim portions of the metal disc between the conductors.

2. The method of electrically connecting the ends of the conductors disposed generally in a circle, the ends of the conductors being in a common plane, to a plurality of electrical terminals disposed within said circle and substantially in said plane, comprising removing the central portions of a sheet of metal to form a plurality of integrally joined ribbons, the ribbons extending in a predetermined direction and having predetermined lengths corresponding to the directions and lengths of lines, in said plane, between the conductors and terminals, then welding one end of each of said ribbons to one of said terminals, then welding the other end of each of said ribbons to the end of one of said conductors, and finally removing the portions of the metal sheet from between said conductors.

3. An electron discharge device comprising an assembly of electrodes, a header, a plurality of spaced parallel circularly arranged lead-in conductors sealed in said header and projectin perpendicularly from the inner surface of said header, said conductors extending a uniform relatively short distance from the inner surface of said header with their inner ends flattened in a common plane parallel to said header, a plurality of ribbon-like metal connectors disposed in the plane of said inner ends of the conductors and extending in generally radial directions from the said inner ends, each connector being welded at its inner end to one of the electrodes and at its outer end to one of the conductors with a fiat side of said connector resting on the flat inner end of said conductor.

4. An electron discharge device comprising envelope, a glass disc closing one end of said envelope, a plurality of circularly arranged parallel lead-in conductors sealed in said disc, the inner ends of said conductors being fiat and terminating a uniform distance from said disc in a common plane parallel to said disc, a unitary electrode assembly in the envelope comprising electrodes with terminals at said common plane, a plurality of ribbon-like metal connectors in the plane through said inner ends of the conductors, each connector being connected at its inner end to a terminal of one of the electrodes of said assembly and with its flat side near the outer end overlapping and welded to the flat inner end of one of said conductors.

5. An electron discharge device comprising a tubular envelope having at one end a transverse header, a unitary electrode assembly inside said envelope comprising a plurality of electrodes extending lengthwise of said envelope with terminals substantially in a common plane parallel to said header and between said assembly and said header, spaced parallel rigid lead-in conductors sealed into and projecting inwardly from said. header lengthwise of said envelope, said lead-in conductors having fiat ends substantially said common plane and displaced from said electrode terminals away from the center of said header and outside said assembly, and a plurality of metal ribbon connectors extending radially of said header and substantially in said common plane with their fiat sides transverse to said leading-in conductors and parallel to said header, the inner end of each connector being joined directly to the terminal of an electrode of said assembly and the outer end of each connector having a flat side lying on and joined to the flat inner end of a leading-in conductor.

6. An electron discharge device comprising an elongated evacuated envelope with a transverse header at one end, a unitary electrode assembly mounted in said envelope and including electrodes extending lengthwise of said envelope with terminals adjacent said header, and a plurality of rigid lead-in conductors sealed through said header and extending into and lengthwise of said envelope, said conductors disposed with their inner ends at points on the circumference of a circle concentric with the longitudinal axis or" said assembly and of a diameter greater than the Width of said assembly, the inner ends of said conduc-- tors being flat in a common plane between said assembly and said header, and ribbon straps extending outwardly in said common plane from said electrode terminals with fiat sides near their outer ends lying upon and joined to the flat inner ends of said conductors.

7. An electron discharge tube mount comprising a header, a plurality of rigid conductors sealed through said header and projecting perpendicularly from the inner face of said header at points around a common center, said conductors having flat inner ends in a common plane parallel to said header, metal ribbon connectors with a flat side near their outer ends overlapping and secured to the flat inner ends of said conductors, said connectors projecting toward said common center with their fiat sides parallel to the inner face of said header, and a unitary electrode assembly narrower than the diametrical spacing of said conductors and having electrodes with terminals between said assembly and said header and secured directly to the inner ends of said connectors.

CARL HERZOG. 

